Dan Brown had no idea that the tenant who rented his renovated farmhouse would sublet it to someone who turned it into a marijuana grow house, causing thousands of dollars in damage.

There were chunks of plaster missing from the ceiling where lights had been hung, soil clogging drains beneath the house and duct work that needed repair, Brown said.

And behind a washer-dryer unit, a 220-volt outlet had been removed, exposing live wires.

Brown discovered it when he pulled the unit away from the wall. “If I would have grabbed that, I would have been dead. It scared me to death.”

Renting to those who are growing marijuana — legally or not — can be a tricky business for landlords and holds dangers for tenants as well, said Rich Green, manager of Housing Guru.

The company connects people who want to grow weed legally with landlords willing to allow them to do so.

Housing Guru acts as property manager, checking on the property, making repairs and taking care of any issues that arise.

Green said Housing Guru is managing properties all along the Front Range. Tenants range in age from 24 into their 60s, Green said. They include accountants, scientists, even a police officer.

During the four years the company has been in existence, Green has heard numerous stories like Brown’s.

Grow rooms require a lot of ventilation to prevent mold. To ready a home for the grow can require cutting holes in walls, installing air conditioning units, fans and duct work, all of which can lead to eviction if done without the landlord’s knowledge.

Housing Guru vets prospective tenants, assuring they have a verifiable stream of income, references that check out, and good rental and property histories. The company also runs court checks to search for legal judgments against them, Green said.

Demand for rentals where pot can be grown is soaring in Colorado, where marijuana — both medical and recreational — is sold legally, and the law allows residents to grow their own plants.

Patients on the state’s medical marijuana registry are typically authorized to grow six marijuana plants — with no more than three of those ready for harvest at any given time. But doctors can recommend that patients grow more plants.

Legislation passed last year restricts medical marijuana caregivers, who grow pot on behalf of patients, to 99 plants, said Mark Salley, Colorado Department of Health and Environment spokesman.

While Denver and some other cities allow residents no more than 12 marijuana plants, other jurisdictions have varying limits on the number of plants allowed in homes.

Varying limits can create confusion. “Under the law, you have home grows that look like businesses, with no license, no testing,” said Marijuana Industry Group executive director Michael Elliott. “While there are definitely legitimate ways of growing in your home, it is important to remember it is illegal to sell it to anybody.”

Green has heard complaints from tenants about landlords who kept their deposits, saying the grows violated terms of their leases, or who changed locks to keep them out of the homes. Some have demanded a cut of any profit on the plants, despite the fact that the law doesn’t allow sales of marijuana grown for private use in a home.

Some landlords are hesitant to rent to even the most upstanding tenant who wants to grow cannabis “because they have heard the horror stories,” Green said.

Dan Fortune, a landlord who rents out more than 20 properties in the state, said tenants in all of them grow their own weed.

He was leery of renting to growers before getting involved with Housing Guru.

He did some research, learning that tenants are willing to pay higher than market-rate rents to have a home where they can grow with the landlord’s knowledge.

He started with one property, and then began replacing tenants who moved out with others who wanted to grow, he said.

Fortune said the tenants who grow in his properties are among the best he has had.

Because they are engaged in an activity that many people frown upon, they are quiet.

“There is little turnover, and when someone leaves, Housing Guru tends to replace them before there is a vacancy,” he said. “The risk profile is very low.”

A general assignment reporter for The Denver Post, Tom McGhee has covered business, police, courts, higher education and breaking news. He came to The Post from Albuquerque, N.M., where he worked for a year and a half covering utilities. He began his journalism career in New York City, worked for a pair of community weeklies that covered the west side of Manhattan from 14th Street to 125th Street.

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